Temperature-controlling device for furnaces.



No. 874,781. PATENTED DEC. 24, 1907. A. G. MATHER 5; B. G. SHAW. EMPBRATURB OONTRQLLING DEVICE FOR FURNACES.

APPLICATION FILED APR. 7, 1905. RENEWED 1107.14, 1907.

I VV a A TTURNE temperature control mnrn snares rii'rrrr ALLAN c. MATHER AND n'nnnsr o. SHAW, or MILWAUKEE/WISCONSIN.- I

TEMPERATURE-OONTROLLING DEVICE FOR 'FURNCES.

Application filed April 7, 1905. Serial No.

To all whom it may concern:

Specification of Letters Patent.

Patented Dec. 24, 1907.

254308. Renewed llovcmber' 14. 1907.. Serial No. 402,210.

provided with a notch 28 near one end,-in

Be it known that we, ALLAN G. MATHER which the edge of the disk 20 is engaged, so and Ennnsr C. SI1AW,cit-izcns of the United 1 States, residing at Milwaukee, county of Milwaukee, and State of-VVisconsin, have invented new and useful Improvements in iemperature-Controlling Devices for Furnaces, of which the following istion. .i

Our invention relates to improvements in ling devices forfurnaccs. object of our invention is to provide reliable electromagnetic mechanism, having a thermostatic circuit closer for controllin the operation of a motor which is connected to open and close the draft and check dampers of a furnace in alternation.

In the following description reference is had to the accompanying drawings, in which Figure 1 is a front elevation of our inventionwith part of the casing removed. Fig. 2 is a horizontal sectional view drawn on line a: x of Fi 1., Fig. 3 is a general view illustrating the application of our inventionto a furnace.

1 is a. driving shaft extending throu h a box or casing 2 and provided with cran s3 & 4 on its projecting ends, which are connected respectively with a' check damper 5 and draft damper 6 by means of cords or chains 7, the latter being preferably passed over suitable guidepulleys at 8, as shown in Fig. 3., The cranks 3 6t 4 roject in opposite directions from the shalt 1, so that the dampers 5 & fi'willbe o ened andclosed in alternation. A sprocliet wheel' 10 is loosely mounted on the shaft 1 and is rovided with a clutch member 11,- whic is adapted to engage a clutch memberlZ, fixed on the shaft 1 whereby the shaft 1 may be driven in one direction from the sprocket The clutch members" are arranged to slip when the motion of the wheel 10.

sprocket wheel 10 is reversed and the sprocket wheel 10 is normally held inposition with the clutch members in engagement by means of a spring 13. The sprocket wheel is driven by a weight-14 through a chain 15, which asses around a suitable ulley lfi, connects with the weight 14 and a so over the wheel 10. A disk 20 is driven from the shaft 1 through the medium of the gear wheel21 pinion 22, gear wheel 23, pinion 24; and shaft 25, the disk 20 being'mounted upon the latter. The parts are, however, normally held against movement by means'of a brake lever 27, which is a specificaof the same,

that when the other end of the lever is depressed, the opposing sides of the notch 28 will be brought into binding engagement with the disk to hold it against rotation. The lever 27, at a oint distant from the notch 28, is

connects with an armature bar 30 by means of an adjustable screw threaded post 31, so that this end of the lever may be raised or lowered by means of said armature bar 38. The notched end of the lever is loosely supported by an insulated rest 33.

The armature bar 30 isactnated by gravity other direction by electro magnets 35, an electrical circuit through said magnets being closed b means of a thermostatic switch 36 operatinglietween contact terminals 37 and 38 respectively and the connections being such that when the thermostatic switch'36 contacts with either of the terminals 37 and 38, an electrical 1 circuit will be closed through the magnet 35' from a source of electrical energy is resented in the drawings by a battery 39. 1 "s battery has one pole connected with the ther-.

mostatic switch 36 by means of a conductor 10. A conductor 41 of opposite polarityleads from the battery to the electro magnet coils and. through them to the frame or box 2. The terminals 37 & 38; are electrically connected by means of conductors 43 6t 44 with commutator brushes 45 80-46 respectively, the latter'being mounted in, but insulated from the box 2. & 46 are arranged to bear upon a hub 47 of the clutch member 12,

section of insulation 49 is located in each-of these grooves, whereby7 the circuit will be broken between the hu 47and a registering brush when the corresponding section of in- 100. and the. hub 47. The insulation 49 which is on the opposite sulation is interposed between such brush registers with the brush 45 These brushes 45 (the hub being pro- -vided. with slight grooves for the reception of the brushes) and a comparatively short side of the hub 47 from that whi'chregistersf with the brush 46,

the brushes will be broken alternately during the rotation of shaft 1, and will be broken j so that the circuit through once through each brush during one com-4 plete rotation .of the shaft. i v

Assuming the parts to be in the position in which they are shown in Figs. 1 & 3,"1t

1-10 will be observed that the draftdo'orfi'is f open and the thermostatic swit'ch36 is out terminal 37, conductor 43, commutator brush 46, hub 47 and the frame, the electro magnet, and conductor 41, thus energizing the magnets, lifting the armature bar 30 and l lever 27 and releasing the disk 20, whereupon the weight 14 will actuate the shaft 1 until the brush 46 registers with the eorres onding insulation 49, which separates t e ectrically from the hub 47, thus breaking the circuit and permitting the armature bar to drop and set the brake. on the disk 20; the

Shaft 1 having completed a one-half revoution, the damper 6 will then be closed and the damper 5 opened, thus checking the lire in the furnace.

As the heat decreases, the switch 36 slowly moves across the intervening space until it contacts with the terminal 38, whereupon the circuit is again closed, but this time it is closed through the commutator brush 45, and the shaft 1 is permitted to rotate another one-half revolution, when the circuit is '8. am broken by insulation 49, registering with the brush 45,the dampers being I meanwhile restored to the position in which they are shown in Fig. 3.

ters Patent is,

The weight 14 may 'be manually raised from time to time by pulling upon the free end of the chain 15.

Having thus described our invention what we claim as new and desire to secure by Let- 1. The combination with the draft and check dampers of a furnace, of a crank shaft provided with op ositely projecting cranks connected with tie respective dampers, a sprocket Wheel loose on the crank shaft and rovided with a one-way acting clutch incur-4 er, a weight provided with a sprocket wheel, a sprocket chain passing around said sprocket wheels and connected at one end to a fixed point of sup ort, a clutch member fixed on said crank s aft and adapted to be engaged by the clutch member on the sprocket wheel when the latter is turned in the direction of the pull exerted by the weight, a spring arranged to normally hold said clutch members in mutually engaging contact, a brake mechanism normally preventing the rotation of said crank shaft, a

thermostatic switch, and an electrically operated device for releasing said l-u'ake mechanisinwhen the circuit is closed by said switch, and devices carried by the crank shaft for breaking said electrical circuit.

2. The combination with the draft and check dampers-of a furnace: of a motorarranged to open and close the said dampers in succession; a rotor disk driven by said motor; and a gravity actuated brake lever provided with a notch in which the margin of said disk is entered: said brake lever being 'pivotally supported at one end near the notch and i'lormally adapted to drop by gravity to an angular position with the sides of said notch binding upon the disk, an elec tromagnet provided with a movable armature; a screw adjustably connecting said armature with the brake level; a thermostatic switch for closing electrical circuits through the electro-magnet; and means, operated by the motor, for breaking such circuits.

3. The combination with the draft and check dampers of a furnace of a crank shaft provided with oppositely disposed cranks connected to the respective dampers, fast and loose clutch members mounted on the crank shaft, a sprocket wheel mounted on the loose clutch member, a weight provided with a corresponding sprocket wheel, a chain passed around said sprocket wheels and having one end connected with a fixed point of support above the weight, a thermostatic switch, and means, in operative relation thereto, for releasing and holding the crank shaft, said clutch members being arranged for motion transmitting engagement in one direction only, whereby said weight may be periodically lifted by pulling upon the sprocket chain in the opposite direction without operating the crank shaft.

ln testimony whereof we allix our signatures in the presence of two witnesses.

ALLAN G. MA'lll Elt. ERNEST SHAW.

Witnesses Lnvmusrr W nnmnn, .las. 13. Enwiu. 

